Lewis Hamilton has expressed his total confidence in Ferrari after the Italian Formula One team's double disqualification in China.

The cars of seven-time world champion Hamilton and teammate Charles Leclerc failed post-race technical checks at the second round of the season in Shanghai after they finished sixth and fifth respectively.

"I saw someone said something about whether I'm losing faith in the team, which is complete rubbish," Hamilton, winner of the Shanghai sprint race, told reporters on Thursday ahead of the Japanese Grand Prix.

"I have absolute 100 per cent faith in this team," added the 40-year-old Briton, who joined in January from Mercedes.

"There was obviously a huge amount of hype at the beginning of the year. I don't know if everyone was expecting us to be winning from race one and winning the championship in our first year.

"That wasn't my expectation. I know that I'm coming into a new culture, a new team and it's going to take time."

Leclerc was disqualified after his car was found to be one kilogram below the 800kg minimum weight while Hamilton's had excessive skid wear.

Ferrari team boss Fred Vasseur suggested a leaking water bottle could have accounted for some of Leclerc's problem, which had initially been attributed to excessive tyre wear from a one-stop strategy.

"The tyres are only part of the explanation. We also lost a litre of water with Charles's drink bottle leaking. The loss of weight is always an addition of many small factors," he told L'Equipe.

The Frenchman said Ferrari were playing with fine margins as they fought to match leaders McLaren on performance.

"The aim of the game in F1 is to push yourself to the limit of all parameters, everywhere. To get to the last gram of weight, to get to the last tenth of a millimetre of the skid, to get to the last millimetre of wing deformation.

"So it's certain that the more pressure you're under, the more intense the fight, the closer you need to get to these limits and the more risks you take."